Field of the Invention
The present invention relates to a technology of synthesizing a plurality of pieces of audio data.
Priority is claimed on Japanese Patent Application No. 2013-218487, filed on Oct. 21, 2013, the content of which is incorporated herein by reference.
Description of Related Art
IC recorders which record audio information for preparing the minutes of interviews and meetings have been known. The IC recorders include microphones, and are capable of recording the audio information as digital audio data. The audio data recorded by the IC recorders can be reproduced by electronic devices such as personal computers.
Meanwhile, the IC recorders have been used in a variety of applications such as recording of sounds generated in nature, for example, sounds of wind and waterfalls, and chirp of insects, recording of engine sounds played in motor sports, air shows, and the like, and recording of music sounds generated in concerts and by musical instruments being practiced, as well as in business applications. When the IC recorders are mainly used for hobbies as described above, high-quality recording capable of achieving sound localization, that is, a sensation of three-dimensional spatial sounds is desired.
In the above case, it is preferable to perform stereo recording. In the stereo recording, recording is performed in a state in which two microphones are installed while being apart by a suitable distance. However, there are many cases of troublesome treatment such as handling of microphone cables. If a wireless connection is used instead of using the cables, there is no need to handle and install the cables, but it is difficult to synchronize two microphones.
Japanese Unexamined Patent Application, First Publication No. 2004-193868 discloses a synchronization method of audio data which is transmitted from a transmission device to a plurality of output devices. In this method, the times of respective devices are synchronized with a reference time, and a time at which audio data is output from the output devices is determined, based on a time at which the transmission device makes a request of timestamps to the output devices and a time at which the transmission device receives responses from the output devices.